"Upstream" and Republished prod library

I need some assistance wrapping my head around the Upstream concept related to published and Republished libraries.

I had a couple failed publishes to Prod and had to rollback / republish a known good library.  How can I get back to that point to build a new release candidate?  I don't want what's in the failed publishes to be considered in the new build.

Thanks for ideas and suggestions.